Available on request
after we have determined that your research is one that I can assist you with.

References:

Available upon
request.

Much of my work is
confidential. I will be happy to supply any potential client with references
after it is determined that I can help you and that I am available. To protect
my clients' privacy, however, I will never send out a reference list with their
contact information before I am confident that a person is serious about a
research commitment with me.